Enhancement of phentolamine by nitrates in patients with congestive heart failure.
Phentolamine dilates the resistance bed and to a lesser degree the capacitance bed, while the nitrates have the opposite action. Therefore, in 7 patients with congestive heart failure due to congestive cardiomyopathy, hemodynamic measurements were made using a Swan Ganz thermodilution catheter and cardiac output computer. The patients received 5 mg of an IV infusion of phentolamine administered at 0.3 mg/minute. At the end of the infusion, the pressures and cardiac output were obtained. Then, 2 1/2 inches of nitroglycerin ointment was applied to the chest, and the hemodynamic parameters were obtained 30 minutes later. Phentolamine produced a significant reduction in the right and left ventricular filling pressures and a significant increase in the cardiac output. The hemodynamic effects of phentolamine are known to persist for an hour or longer. The addition of nitroglycerin ointment led to a further reduction in the right and left ventricular filling pressures. Thus, the combination of phentolamine and nitrates can be effectively used in the treatment of congestive heart failure.
D001794:Blood Pressure / Q000187:drug effects; D002302:Cardiac Output / Q000187:drug effects; D004359:Drug Therapy, Combination; D005260:Female; D006333:Heart Failure / Q000188:drug therapy*; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009566:Nitrates / Q000627:therapeutic use*; D005996:Nitroglycerin / Q000627:therapeutic use*; D010646:Phentolamine / Q000627:therapeutic use*; D013318:Stroke Volume / Q000187:drug effects
D009566:Nitrates; D005996:Nitroglycerin; D010646:Phentolamine